(19)
(11) EP 0 878 916 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
22.10.2003 Bulletin 2003/43

(43) Date of publication A2:
18.11.1998 Bulletin 1998/47

(21) Application number: 98108895.8

(22) Date of filing: 15.05.1998
(51) International Patent Classification (IPC)7: H04B 1/40
(84) Designated Contracting States:
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
Designated Extension States:
AL LT LV MK RO SI

(30) Priority: 16.05.1997 JP 14114197

(71) Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
Kadoma-shi, Osaka 571-8501 (JP)

(72) Inventor:
  • Yamamoto, Naoyuki
    Yokohama-shi, Kanagawa 240 (JP)

(74) Representative: Grünecker, Kinkeldey, Stockmair & Schwanhäusser Anwaltssozietät 
Maximilianstrasse 58
80538 München
80538 München (DE)

   


(54) Dual-band data communication device


(57) The direction of rotation of the phase of signals in a dual-band digital demodulation processing means 110 and a dual-band digital modulation processing means 112 is controlled in accordance with a band selection control means 113 for selecting a first-band local oscillator 105 or a second-band local oscillator 106 so as to be reversed an even number of times in total. The direction of rotation of the phase of signals is controlled to return its original direction of rotation finally even if there is a difference between the first and second bands in the high/low relationship between the transmission/reception frequency and the local oscillation frequency. Accordingly, reception data can be outputted properly, and a transmission wave can be outputted properly. Since it is possible to attain transmission and reception properly in any high/low relationship between the transmission/reception frequency and the local oscillation frequency, the degree of freedom in selecting the local oscillation frequency can be increased.






Search report